Reversing car-seat base



Sept. 24, 1940. O, E, H||

REVERSING CAR-SEAT BASE Filed A ril s, 1938 2 Sheets-Shem l Sept. 24, 1940.. o. E. HILL REVERSING CAR-SEAT BASE 2 Sheeis-Shezax 2 Filed April 8, 1938 Patented Sept. 24, 1940 UNITED STATES Pram OFFICE REVEESING CAR-SEAT BASE Oiva E. Hill, Gardner, Mass, assigncr to Heywood- M Wakefield Company, Gardner, Masa, a corporation of Massachusetts Application April 8, 1938, Serial No. 200,825

8 Claims.

This invention relates to a reversing car-seat base by which a seat may be swung about a vertical axis from one position of use through an angle of 180 to a reversed position. During its reversing movement the seat is guided in such a manner as to cause the axis of rotation to shift away from the vehicle wall during the initial portion of the reversing movement and to approach the wall during the final portion of the movement. Various mechanisms have heretofore been devised for accomplishing this general purpose.

It is an object of the present invention to provide a mechanism which is characterized by great simplicity ofstructure and effectiveness in shifting the axis of rotation rapidly away from the wall during the initial portion of the reversing movement. The embodiment of the invention hereinafter described is also characterized by strength and rigidity as well as lightness of weight so that the mechanism is well adapted for vehicles where minimum weight is important, as, for example, in busses and aeroplanes;

For a more complete understanding of the invention, reference may be had to the following description of an embodiment thereof, and to the drawings of which Figure l is an end elevation of a vehicle seat embodying the invention.

Figure 2 is a diagrammatic plan view of a portion of a vehicle showing the relation of a seat embodying the invention to the vehicle wall and to adjacent seats.

Figure 3 Ba sectional view on the line 3-3 of Figure 2.,

Figure 4 is a sectional View on the line 4-4 of Figure 3.

Figure 5 is a sectional View on the line 5-5 of Figure 3.

Figure 6 is a sectional View on the line 66 of Figure 3. a

Figure '7 is a diagrammatic plan View of the cam mechanism shown in Figure 6, the parts being shown on a smaller scale and in different positions.

' Figure 8 is a view similar to Figure 7 but showing the parts in different positions.

Figure 9 is a fragmentary plan view of a modilied form of cam follower and a portion of a cam edge.

The invention may be embodied in a seat or chair including a pedestal or supporting frame ill adapted to be secured to the floor. This pedestal has a horizontal top member it? which, as indicated in Figures 3 and 6, may include a plate i4 mounted between a pair of angle rails l6 and it, the upper surfaces of the plate and angle rails being flush. Slidable on the upper surface of the top member I2 is a seat carriage which includes a plate ill and a frame '22 which may be tubular, if desired, for lightness and strength.

iii

This frame supports a seat member 24, arm rests 26 and back members 28, as well as any other desired accessories orparts for a pair.

Guiding means are provided for guiding the reversing movements of the seat and its carriage on the top member l2. To this end, the plate I4 is provided with an aperture 30 defining three cam edges 32, 34 and it. These cam edges are concave and arcuate and are equal in length and in curvature. The cam edges are so arranged that they meet at their ends and their chords form an equilateral triangle. Cooperating with these cam edges area pair of cam followers 4!] and 42 which are secured to the seat carriage 20 and project down through the aperture 30 so as to be constantly in. engagement with the cam edges. shown, each of these cam followers includes a six-sided shoe 44 loosely mounted on a central bolt 46, the shoes 44 being the elements'which are in actual contact with the cam edges. The six side faces of each shoe 44 are cylindrical, the radius of curvature of the cylinder being equal to that of the cam edges so that the side faces of the shoes lit the curvature of the cam edges. These shoes thus present surfaces adapted to have interfacial contact with the cam edges over substantial areas so as to minimize wear. As indicated in Figure 3, a spacing sleeve 48 may be provided between each bolt 46 and its shoe 44 so 1 as to permit free rotation of the shoe relative to the bolt. Each bolt also carries a washer 50 beneath the plate M, the washers 5i] acting as holddown elements to retain the seat carriage l2 on the pedestal.

The cam followers 4!! and 42 are preferably connected by a rigid rod or tube 52 below the plate Hi. This stiffens the carriage structure materially and helps to support the cam followers against lateral thrusts resulting from engagement with the cam edges. As shown, the bolts 46 are permanently mounted on the rod or tube 52 and are secured to the carriage 20 by means of suitable nuts 54.

During any reversing movement of the seat, the cam follower shoes 44 slide along the cam edges. For example, as indicated in Figures 6, '7 and 8, the cam follower 42 slides along the cam edge 36 during the initial portion of a reversing movement of the seat, the cam follower 40 remaining at rest until the cam follower 42 has reached the end of the edge 36. The cam follower 42 then remains at rest in the position shown in Figure 7 while the cam follower 44 moves along the edge 32 to the right-hand end thereof. The cam follower 40 then remains stationary in this corner while the cam follower 42 moves from one end of the edge 34 to the other, reaching the position illustrated in Figure 8. It will be observed that, when the seat carriage and the rod 52 move from the position indicated inFigure 6 to that indirod 52 with the abutment member 60.

cated in Figure 8, the cam followers 40 and 42 exchange places. When the seat moves back to its original position, the movements of the cam followers take place in the reverse directions and in the reverse order.

In order to limit the reversing movements of the seat so that it will not move in excess of 180, 2. pair of abutment members and 62 are mounted on the pedestal. The rod or tube 52 has an end portion 64 acting as a stop element arranged to engage the abutment members 60 and E32 and to be stopped thereby. At the opposite end of the tube 52 is a detent element in the form of a plunger 66 adapted to telescope with the end portion of the tube and pressed longitudinally outward by a spring 68. This plunger has a rounded end 10 which is adapted to ride upon the abutment members 50 and 62 so as to hold the seat carriage yieldingly in either of its positions for use. For example, when the seat is in the position indicated in Figure 6, the carriage is positively held against counter-clockwise rotation by the engagement of the end portion 64 of the The carriage is yieldingly held against clockwise rotation by the engagement of the plunger 65 with the abutment member 62. If the seat is turned with sufiicient force in a clockwise direction, the plunger 66 rides on the abutment member 62 and is pressed inwardly against the spring 68 until it passes the abutment member 62. The seat thereupon rotates freely in a clockwise direction until the rod 52 approaches the position shown in Figure 8. The plunger 66 then snaps past the abutment member 60 but the member 64 prevents further clockwise movement of the carriage by positively engaging the abutment member 62. Reversing movements of the seat and seat carriage are thus limited to 180 of rotation.

A modified form of the follower is illustrated in Figure 9, this follower having a cylindrical shoe (6 loosely mounted on each bolt 46 so as to act as a roller engaging the cam edges. Each pair of cam edges may be rounded off as at 18 near the point of intersection to accommodate the roller 16, the curvature of the edge at the point 18 being preferably equal to the curvature of the roller 16.

Various modifications and changes may be made in the details of structure herein shown and described, without departing from the spirit or scope of the invention defined in the following claims.

I claim:

1. A reversing car-seat base, comprising a stationary supporting frame having a flat top member, a seat carriage including a member slidable on said top member, and means for guiding the reversing movement of the seat, said means comprising three concave arcuate cam edges of the same length and curvature on one of said members, and a pair of cam followers on the other said member engaging said cam edges.

2. A reversing car-seat base, comprising a stationary supporting frame having a fiat top member, a seat carriage including a member slidable on said top member, and means for guiding the reversing movement of the seat, said means comprising three arcuate cam edges on one of said members, said edges being arranged so that the chords of their arcs form an equilateral triangle, and a pair of cam followers mounted on the other said member and engaging said edges, said cam followers being spaced apart a distance approximately equal to the length of one of said chords.

3. In a reversing car-seat base, a stationary frame having a flat horizontal member, a seat carriage having a member slidable on said horizontal member, one of said members having an aperture therein bounded entirely by concave cam edges, the other said member having a pair of cam followers mounted thereon and in constant engagement with said cam edges, said cam edges being so shaped that said followers exchange places when the seat is reversed.

4. A reversing car-seat base, comprising a pedestal including a horizontal plate having a triangular aperture therein, the side edges of said aperture consisting of three similar arcs, a seat carriage movable on said pedestal, and a pair of members projecting from said carriage and into said aperture to ride along the edges thereof, said members being spaced to fit snugly in any two of the corners of said aperture at the same time.

5. Apparatus of the class described, comprising a stationary horizontal plate having an aperture therein bounded by three similar concave arcuate edges of equal length and curvature, a reversible member movable on said plate, said member having a pair of cam followers mounted thereon and in engagement with said edges, each said follower comprising a six-sided shoe, the side faces of which have a convex curvature equal to the curvature of said edges.

6. A reversing car-seat base, comprising a pedestal including a horizontal top member having an aperture therein defining cam edges, a seat carriage slidable on said top member, a pair of cam followers mounted on said carriage and extending down through said aperture to engage said cam edges, a rigid rod connecting said cam followers below said top member, and a pair of fixed abutment members engageable by one end portion of said rod to limit reversing movement of said carriage.

'7. A reversing car-seat base, comprising a pedestal including a top member having an aperture therein defining cam edges, a seat carriage slidable on said top member, a pair of cam followers mounted on said carriage and projecting through said aperture to engage said cam edges, a rigid rod connecting said followers below said top member, a pair of abutment members mounted below said top member and engageable by one end portion of said rod to limit the reversing movements of said carriage, and a spring-pressed extension at the other end of said rod arranged for engagement with said abutment members to hold said carriage yieldingly in either of its reversed positions.

8. A reversing car-seat base comprising a stationary pedestal having a fiat top with a three cornered aperture therein defining cam edges, two of the corners of said aperture being arranged substantially on the front-to-rear median of the pedestal, a seat carriage slidable on said top, a pair of cam followers mounted on said carriage and projecting therefrom into said aperture to engage said cam edges, said followers being arranged to occupy said two corners respectively when the seat is in one of its positions for use, stop means for preventing movement of one of said followers from its corner toward the third corner, and yielding detent means releasably maintaining the other said follower in its corner.

OIVA E. HILL. 

